[Linux-NTFS-cvs] CVS: dynamic-disk/linux/fs/partitions ldm.c,1.56,1.57

[Jakob K. <jk...@us...>]

Changes by: jkemi

Update of /cvsroot/linux-ntfs/dynamic-disk/linux/fs/partitions
In directory usw-pr-cvs1:/tmp/cvs-serv24391

Modified Files:
	ldm.c 
Log Message:

Big cleanup. ldm_create_db_partition() obsolete. 
ldm_validate_partition_table() rewritten. Commenting ( esp. in
ldm_combine_vblks() )



Index: ldm.c
===================================================================
RCS file: /cvsroot/linux-ntfs/dynamic-disk/linux/fs/partitions/ldm.c,v
retrieving revision 1.56
retrieving revision 1.57
diff -U2 -r1.56 -r1.57
--- ldm.c	9 Feb 2002 16:39:33 -0000	1.56
+++ ldm.c	9 Feb 2002 18:10:08 -0000	1.57
@@ -350,48 +350,38 @@
 	u8 *data;
 	struct partition *p;
-	int i, nr_sfs;
-	BOOL result = FALSE;
-
-	BUG_ON (!bdev);
+	int i;
 
-	data = read_dev_sector (bdev, 0, &sect);
-	if (!data)
+	if ((data = read_dev_sector (bdev, 0, &sect)) == 0)
 		return FALSE;	// FIXME error message?
 
 	if (*(u16*) (data + 0x01FE) != cpu_to_le16 (MSDOS_LABEL_MAGIC)) {
 		ldm_debug ("No MS-DOS partition found.\n");
-		goto out;
+		put_dev_sector(sect);
+		return FALSE;
 	}
-	nr_sfs = 0;
+
 	p = (struct partition*)(data + 0x01BE);
-	for (i = 0; i < 4; i++, p++) {
-		if (!SYS_IND (p) || SYS_IND (p) == WIN2K_EXTENDED_PARTITION)
-			continue;
-		if (SYS_IND (p) == WIN2K_DYNAMIC_PARTITION) {
-			nr_sfs++;
-			continue;
-		}
-		break;
-	}
-	if (nr_sfs) {
-		result = TRUE;
-		ldm_debug ("Parsed partition table successfully.\n");
-	} else {
-		ldm_debug ("Found a basic MS-DOS partition, not a dynamic "
-			   "disk.\n");
+	for (i = 0; i < 4; i++, p++)
+		if (SYS_IND(p) == WIN2K_DYNAMIC_PARTITION)
+			break;
+
+	put_dev_sector(sect);
+	if (i == 4) {
+		ldm_debug(
+		    "Found a basic MS-DOS partition, not a dynamic disk.\n");
+		return FALSE;
 	}
-out:
-	put_dev_sector (sect);
-	return result;
+
+	ldm_debug ("Parsed partition table successfully.\n");
+	return TRUE;
 }
 
 /**
  * ldm_validate_privheads - Compare the primary privhead with its backups
- * @bdev:  Partition device holding the LDM Database
- * @base:  The offset into the device
- * @ph1:   First privhead which we have already validated
+ * @bdev:         Partition device holding the LDM Database
+ * @first_sector: First sector within the device
+ * @ph1:          Memory struct to fill with ph contents
  *
- * We already have the primary privhead from the beginning of the disk.
- * Now we compare the two other copies for safety.
+ * Read and compare all three privheads from disk.
  *
  * Return: TRUE   Success
@@ -399,18 +389,23 @@
  */
 static BOOL ldm_validate_privheads (struct block_device *bdev,
-	unsigned long base, const struct privhead *ph1)
+	unsigned long first_sector, struct privhead *ph1)
 {
 	Sector sect;
 	u8 *data;
 	struct privhead ph2, ph3;
-	struct privhead *ph[3] = {NULL, &ph2, &ph3};
+	struct privhead *ph[3] = {ph1, &ph2, &ph3};
 	const int off[3] = {OFF_PRIVHEAD1, OFF_PRIVHEAD2, OFF_PRIVHEAD3};
 	int i;
 
-	/* Read and parse ph 2 & 3 */
+	/* off[1 & 2] are relative to ph[0]->config_start */
+	ph[0]->config_start = 0;
+
+	/* Read and parse privheads */
 	// FIXME can ph 3 fail on odd-sized disks?
-	for (i = 1; i < 3; i++) {
-		int r;
-		if (!(data = read_dev_sector (bdev, base + off[i], &sect))) {
+	for (i = 0; i < 3; i++) {
+		BOOL r;
+		data = read_dev_sector (bdev,
+			first_sector + ph[0]->config_start + off[i], &sect);
+		if (!data) {
 			printk (LDM_CRIT "Disk read failed.\n");
 			return FALSE;
@@ -424,6 +419,6 @@
 
 	/* Compare privheads */
-	if (!ldm_compare_privheads (ph1, ph[1]) ||
-	    !ldm_compare_privheads (ph1, ph[2])) {
+	if (!ldm_compare_privheads (ph[0], ph[1]) ||
+	    !ldm_compare_privheads (ph[0], ph[2])) {
 		printk (LDM_CRIT "Primary and backup PRIVHEADs don't match.\n");
 		return FALSE;
@@ -460,5 +455,5 @@
 	for (i = 0; i < 4; i++)
 	{
-		int r;
+		BOOL r;
 		if (!(data = read_dev_sector (bdev, base + off[i], &sect))) {
 			printk (LDM_CRIT "Disk read failed.\n");
@@ -503,8 +498,5 @@
 	BOOL result;
 
-	BUG_ON (!bdev || !vm);
-
-	data = read_dev_sector (bdev, base + OFF_VMDB, &sect);
-	if (!data) {
+	if ((data = read_dev_sector (bdev, base + OFF_VMDB, &sect)) == 0) {
 		printk (LDM_CRIT "Disk read failed.\n");
 		return FALSE;
@@ -527,10 +519,7 @@
 {
 	list_t *item;
-	struct vblk *vb;
-
-	BUG_ON (!lh_vl);
 
 	list_for_each (item, lh_vl) {
-		vb = list_entry (item, struct vblk, list);
+		struct vblk *vb = list_entry (item, struct vblk, list);
 		if (vb->obj_id == id)
 			return vb;
@@ -576,49 +565,4 @@
 
 /**
- * ldm_create_db_partition - Create a dedicated partition for our database
- * @hd:            gendisk structure in which to create partition
- * @bdev:          Device to be partitioned
- * @first_sector:  First sector of data on the device
- * @first_minor:   Device minor to be used
- * @ph:            privhead structure to save the Primary PRIVHEAD in
- *
- * Find the primary private header, locate the LDM Database, then create a
- * partition to wrap it.
- *
- * Return: TRUE   The device is a dynamic disk
- *         FALSE  Error, the device may or may not be a dynamic disk
- */
-static BOOL ldm_create_db_partition (struct gendisk *hd,
-		struct block_device *bdev, unsigned long first_sector,
-		int first_minor, struct privhead *ph)
-{
-	Sector sect;
-	u8 *data;
-	BOOL result = FALSE;
-
-	BUG_ON (!hd || !bdev || !ph);
-
-	data = read_dev_sector (bdev, OFF_PRIVHEAD1, &sect);
-	if (!data) {
-		printk (LDM_CRIT "Device read failed.\n");
-		return FALSE;
-	}
-	if (BE64 (data) != MAGIC_PRIVHEAD) {
-		printk (LDM_ERR "Cannot find PRIVHEAD structure.  "
-			"Not a dynamic disk or corrupt LDM Database.\n");
-		goto out;
-	}
-	if (!ldm_parse_privhead (data, ph))
-		goto out;				/* Already logged */
-
-	result = ldm_create_partition (hd, first_minor,
-		first_sector + ph->config_start, ph->config_size);
-out:
-	put_dev_sector (sect);
-	//FIXME ldm_debug here?
-	return result;
-}
-
-/**
  * ldm_create_data_partitions - Create data partitions for this device
  * @hd:            gendisk structure in which to create the data partitions
@@ -958,8 +902,6 @@
 	ldm_get_vstr (buffer + 0x18 + rel_diskid, disk->alt_name,
 		sizeof (disk->alt_name));
-	if (!ldm_parse_guid (buffer + 0x19 + rel_name, disk->disk_id)) {
-		printk ("failed\n"); // FIXME
+	if (!ldm_parse_guid (buffer + 0x19 + rel_name, disk->disk_id))
 		return FALSE;
-	}
 
 	return TRUE;
@@ -1096,5 +1038,5 @@
  * @vb:       In-memory vblk in which to return information
  * @page:     Disk sector page
- * @recycled: Reset record number and count if 1
+ * @recycled: Reset record number and count if TRUE
  *
  * Read a raw VBLK Component object into a more usable vblk structure.
@@ -1110,7 +1052,7 @@
  */
 static BOOL ldm_parse_vblk (const u8 *buffer, int buflen, struct vblk *vb,
-				struct page *page, int recycled)
+				struct page *page, BOOL recycled)
 {
-	BOOL result = FALSE;
+	BOOL result;
 
 	BUG_ON (!buffer || !vb);
@@ -1120,5 +1062,5 @@
 
 	if (MAGIC_VBLK != BE32 (buffer)) {
-		printk (LDM_CRIT "Cannot find VBLK, database may be corrupt.\n");
+		ldm_debug("Not a valid VBLK, missing magic number.\n");
 		return FALSE;
 	}
@@ -1133,57 +1075,58 @@
 
 	if (vb->rec_count == 0) {
-		printk (LDM_ERR "VBLK record count 0 !!\n");
+		ldm_debug("record count is 0, skipping.\n");
 		return FALSE;
 	}
 
-	if (vb->rec_num == 0 && vb->rec_count == 1) {	/* First record */
-		vb->flags  = buffer[0x12];
-		vb->type   = buffer[0x13];
-		vb->obj_id = ldm_get_vnum (buffer + 0x18);
-		ldm_get_vstr (buffer+0x19+buffer[0x18], vb->name,
-			sizeof (vb->name));
-
-		switch (vb->type) {
-		case VBLK_COMP:
-			result = ldm_parse_comp (buffer, buflen, vb); break;
-		case VBLK_DSK1:
-			result = ldm_parse_disk (buffer, buflen, vb); break;
-		case VBLK_DSK2:
-			result = ldm_parse_disk2(buffer, buflen, vb); break;
-		case VBLK_DGR1:
-			result = ldm_parse_dgrp (buffer, buflen, vb); break;
-		case VBLK_DGR2:
-			result = ldm_parse_dgrp2(buffer, buflen, vb); break;
-		case VBLK_PART:
-			result = ldm_parse_part (buffer, buflen, vb); break;
-		case VBLK_VOLU:
-			result = ldm_parse_volu (buffer, buflen, vb); break;
-		default:
-			//printk(LDM_ERR "Unknown VBLK type 0x%02x.\n", vb->type);
-			//result = FALSE; not nec
+	/* If this is part of a multipart vblk, we increase ref. count, and
+	   add pointers to raw data */
+	if (vb->rec_count > 1) {
+		get_page (page);			/* Inc ref. count */
+		vb->vblk.ext.page = page;
+		if (vb->rec_num == 0) {
+			vb->vblk.ext.data = buffer;
+			vb->vblk.ext.size = buflen;
+		} else {
+			vb->vblk.ext.data = buffer + 0x10; /* Skip header */
+			vb->vblk.ext.size = buflen - 0x10;
 		}
+		return TRUE;
+	}
 
-		if (!result)
-			printk (LDM_ERR "Failed to parse a VBLK of type "
-				"0x%02x.\n", vb->type);
-		else
-			//ldm_debug ("Parsed VBLK #%llu (type: 0x%02x) ok.\n",
-			ldm_debug ("Parsed VBLK 0x%llx (type: 0x%02x) ok.\n",
-				 (unsigned long long) vb->obj_id, vb->type);
-
-		return result;
-	}
-
-	get_page (page);            /* Increase the ref count */
-	vb->vblk.ext.page = page;
-	if (vb->rec_num == 0) {
-		vb->vblk.ext.data = buffer;
-		vb->vblk.ext.size = buflen;
-	} else {
-		vb->vblk.ext.data = buffer + 0x10;
-		vb->vblk.ext.size = buflen - 0x10;
+	/* the vblk is in one fragment and ready for processing */
+	vb->flags  = buffer[0x12];
+	vb->type   = buffer[0x13];
+	vb->obj_id = ldm_get_vnum (buffer + 0x18);
+	ldm_get_vstr (buffer+0x19+buffer[0x18], vb->name, sizeof (vb->name));
+
+	switch (vb->type) {
+	case VBLK_COMP:
+		result = ldm_parse_comp (buffer, buflen, vb); break;
+	case VBLK_DSK1:
+		result = ldm_parse_disk (buffer, buflen, vb); break;
+	case VBLK_DSK2:
+		result = ldm_parse_disk2(buffer, buflen, vb); break;
+	case VBLK_DGR1:
+		result = ldm_parse_dgrp (buffer, buflen, vb); break;
+	case VBLK_DGR2:
+		result = ldm_parse_dgrp2(buffer, buflen, vb); break;
+	case VBLK_PART:
+		result = ldm_parse_part (buffer, buflen, vb); break;
+	case VBLK_VOLU:
+		result = ldm_parse_volu (buffer, buflen, vb); break;
+	default:
+		ldm_debug("Unknown VBLK type: 0x%02x.\n", vb->type);
+		result = FALSE;
 	}
 
-	return TRUE;
+
+	if (!result)
+		printk (LDM_ERR "Failed to parse VBLK 0x%llx (type: 0x%02x).\n",
+			vb->obj_id, vb->type);
+	else
+		ldm_debug ("Parsed VBLK 0x%llx (type: 0x%02x) ok.\n",
+			 (unsigned long long) vb->obj_id, vb->type);
+
+	return result;
 }
 
@@ -1196,9 +1139,9 @@
  * Place vblk in correct list by examining type.
  * All extended vblk's are placed in a special list for later processing.
- * Some types gets sorted into it's list.
+ * Partitions and fragments is added in sorted order.
  *
  * Strange vblk's should've been removed in ldm_parse_vblk
+ * This function returns void because it currently can't fail.
  *
- * FIXME return values? void none
  */
 static void ldm_ldmdb_add(struct vblk *vb, struct ldmdb *ldb)
@@ -1206,9 +1149,7 @@
 	list_t *item;
 
-	//FIXME ldm_debugs?
-
-	/* If vb is part of a multiple-record vblk, we sort it into the pool */
-	// FIXME sorted by group and recnum
-	if (vb->rec_count != 1) {
+	/* If vb is part of a multiple-record vblk, we sort it into the pool by
+	   group and record number */
+	if (vb->rec_count > 1) {
 		list_for_each (item, &ldb->v_extpool) {
 			struct vblk *v = list_entry (item, struct vblk, list);
@@ -1223,5 +1164,6 @@
 	}
 
-	/* Put vblk into the correct list */
+	/* Put vblk into the correct list. A default case is not needed since
+	   vb is already sanity-checked in ldm_parse_vblk() */
 	switch (vb->type) {
 	case VBLK_DGR1:
@@ -1251,8 +1193,4 @@
 		list_add_tail(&vb->list, &ldb->v_part);
 		return;
-	/* This can't happen, gets checked in ldm_parse_vblk()!! */
-	default:
-		// FIXME BUG?
-		return;
 	}
 }
@@ -1272,9 +1210,9 @@
 static int ldm_combine_vblks (struct ldmdb *ldb)
 {
-	struct vblk *vb = NULL;
+	struct vblk *vb;
 	list_t *item;
 	int rec, nrec, group;
 	u8 *data = NULL;
-	u8 *tptr;
+	u8 *ptr;
 
 	if (list_empty(&ldb->v_extpool))
@@ -1286,23 +1224,20 @@
 	group = list_entry(ldb->v_extpool.next, struct vblk, list)->group;
 
-	/* Sanity check records */
+	/* Count number of continuous fragments in first group found */
 	list_for_each (item, &ldb->v_extpool) {
 		struct vblk *v = list_entry (item, struct vblk, list);
-		if (v->rec_num!=rec || v->rec_count!=nrec || v->group!=group) {
-			// FIXME log?  no, implies found next group
+		if (v->rec_num!=rec || v->rec_count!=nrec || v->group!=group)
 			break;
-		}
 		rec++;
 	}
 
-	/* Sanity check records */
-	/* Remove from list if not sane */
+	/* If the number of continuous fragments in group isn't equal to the
+	   expected number, we remove all fragments in the group from the list */
 	if (rec != nrec) {
 		ldm_debug("Group: %d (%d records) is corrupt\n", group, nrec);
 		list_for_each (item, &ldb->v_extpool) {
 			struct vblk *v = list_entry (item, struct vblk, list);
-			if (v->group != group) {
+			if (v->group != group)
 				break;
-			}
 			list_del(&v->list);
 			put_page(v->vblk.ext.page);/* Decrease the ref count */
@@ -1312,33 +1247,30 @@
 	}
 
-	/* Allocate memory buffer */
-	data = kmalloc (ldb->vm.vblk_size * nrec, GFP_KERNEL);
-	if (!data) {
+	/* Allocate memory buffer to hold the concatenated data */
+	if ((data = kmalloc (ldb->vm.vblk_size * nrec, GFP_KERNEL)) == 0) {
 		printk (LDM_CRIT "Out of memory in combine vblks.\n");
 		return -1;
 	}
 
-	/* Concatenate data */
-	tptr = data;
+	/* The first fragment will become the new vblk entry */
+	vb = list_entry (ldb->v_extpool.next, struct vblk, list);
+
+	/* Concatenate data. Processed fragments are removed from list and
+	   freed (except for the first one which we keep). */
+	ptr = data;
 	list_for_each (item, &ldb->v_extpool) {
 		struct vblk *v = list_entry (item, struct vblk, list);
-		if (v->group != group) {
-			// FIXME error condition? log?
-			break;
-		}
+		memcpy(ptr, v->vblk.ext.data, v->vblk.ext.size);
+		ptr += v->vblk.ext.size;
 
-		memcpy(tptr, v->vblk.ext.data, v->vblk.ext.size);
-		tptr += v->vblk.ext.size;
 		list_del(&v->list);
 		put_page(v->vblk.ext.page);/* Decrease the ref count */
 
-		if (v->rec_num == 0)
-			vb = v;
-		else
+		if (v != vb)
 			kfree(v);
 	}
 
 	/* Add record to ldmdb */
-	if (ldm_parse_vblk(data, (int)(tptr-data), vb, NULL, 1))
+	if (ldm_parse_vblk(data, (int)(ptr-data), vb, NULL, TRUE))
 		ldm_ldmdb_add(vb, ldb);
 
@@ -1379,5 +1311,5 @@
 		}
 
-		/* Loop through every entry in sector */
+		/* Loop through all entries in sector */
 		for (i = 0; i < perbuf; i++) {
 			const u8 *block = data + i*ldb->vm.vblk_size;
@@ -1399,5 +1331,6 @@
 			}
 
-			if (ldm_parse_vblk (block, ldb->vm.vblk_size, vl, sect.v, 0))
+			if (ldm_parse_vblk (block, ldb->vm.vblk_size,
+			    vl, sect.v, FALSE))
 				ldm_ldmdb_add(vl, ldb);
 
@@ -1405,5 +1338,4 @@
 		}
 
-		//FIXME any vblks we need will have addref'd the page
 		put_dev_sector(sect);
 		if (failed)
@@ -1412,6 +1344,8 @@
 
 	/* Combine and parse vblk entries with multiple records */
-	while (ldm_combine_vblks(ldb) == 0);
-	// FIXME doesn't bail out on failure
+	while ( (i = ldm_combine_vblks(ldb)) == 0 ) {}
+
+	if (i < 0)		/* already logged */
+		return 0;
 
 	return TRUE;
@@ -1432,14 +1366,9 @@
 {
 	list_t *item;
-	struct vblk *vb;
-
-	BUG_ON (!ldb);
 
 	list_for_each (item, &ldb->v_disk) {
-		vb = list_entry (item, struct vblk, list);
-		if (memcmp (vb->vblk.disk.disk_id, ldb->ph.disk_id, GUID_SIZE))
-			continue;
-
-		return vb;
+		struct vblk *v = list_entry (item, struct vblk, list);
+		if (!memcmp(v->vblk.disk.disk_id, ldb->ph.disk_id, GUID_SIZE))
+			return v;
 	}
 
@@ -1456,12 +1385,9 @@
 {
 	list_t *item;
-	struct vblk *vl;
 
-	if (!lh_vl)
-		return;
 	list_for_each (item, lh_vl) {
-		vl = list_entry (item, struct vblk, list);
+		struct vblk *v = list_entry (item, struct vblk, list);
 		list_del (item);
-		kfree (vl);
+		kfree (v);
 	}
 }
@@ -1503,18 +1429,24 @@
 		return 0;
 
-	/* Create the LDM database device. */
-	if (!ldm_create_db_partition (hd, bdev, first_sector, first_minor, &ldb.ph))
-		goto cleanup;			/* Already logged */
+	/* Parse and check privheads. */
+	if (!ldm_validate_privheads (bdev, first_sector, &ldb.ph))
+		return -1;
 
 	/* All further references are relative to base (database start). */
-	base = hd->part[first_minor].start_sect;
+	base = first_sector + ldb.ph.config_start;
+
+	/* Parse and check tocs and vmdb. */
+	if (!ldm_validate_tocblocks (bdev, base, &toc) ||
+	    !ldm_validate_vmdb      (bdev, base, &ldb.vm))
+	    	return -1;
 
-	/* Parse and check: backup privheads; tables of contents; vmdb. */
-	if ((!ldm_validate_privheads (bdev, base, &ldb.ph))  ||
-	    (!ldm_validate_tocblocks (bdev, base, &toc))     ||
-	    (!ldm_validate_vmdb      (bdev, base, &ldb.vm)))
+#if 1
+	// FIXME: Why do we wan't this partition ??
+	/* Create the LDM database device. */
+	if (!ldm_create_partition (hd, first_minor++, base, ldb.ph.config_size))
 		goto cleanup;
+#endif
 
-	/* Initialize vblk list in ldmdb struct */
+	/* Initialize vblk lists in ldmdb struct */
 	INIT_LIST_HEAD(&ldb.v_dgrp);
 	INIT_LIST_HEAD(&ldb.v_disk);
@@ -1536,5 +1468,5 @@
 
 	/* Finally, create the data partition devices. */
-	if (ldm_create_data_partitions (hd, first_sector, first_minor + 1,
+	if (ldm_create_data_partitions (hd, first_sector, first_minor,
 				      &ldb, disk)) {
 		ldm_debug ("Parsed LDM database successfully.\n");